3 of 8As with the Mazda CX-5 compact crossover, the Mazda 6 line unveiled at the Paris motor show incorporates engine, transmission, body and suspension improvements with an eye toward fuel economy.

Photo by Mazda

4 of 8Paris motor show attendees have the chance to check out the Mazda 6 wagon's interior. Folding rear seats provide plenty of cargo space.

Photo by Mazda

5 of 8Like what you see? Unfortunately, neither the Mazda 6 wagon nor the i-ELOOP system seen at the Paris motor show are slated to head stateside.

Photo by Mazda

6 of 8Another view of the Paris motor show debut of the Mazda 6 wagon, just after the silk was pulled.

Photo by Andrew Stoy / Autoweek

7 of 8The Mazda 6 wagon makes its global debut on the stage at the Paris auto show.

Photo by Andrew Stoy / Autoweek

8 of 8Mazda chairman and CEO Takashi Yamanouchi gives an overview of the company's i-Eloop capacitor-based brake regeneration system at the Paris auto show.

Photo by Andrew Stoy / Autoweek

Mazda showed off its new Mazda 6 wagon today at the Paris motor show, adding a bit of convenience to the latest vehicle that receives the company's SkyActiv treatment. As in the CX-5 compact crossover, SkyActiv technologies in the Mazda 6 include engine, transmission, body and suspension design changes that are meant to improve fuel economy.

Of more interest is Mazda's new brake energy regeneration system, termed “i-ELOOP” (intelligent Energy Loop.) The system uses a capacitor to store electricity generated during deceleration and braking to power the vehicle's electrical systems. Reusing that energy lessens the load on the alternator and improves fuel economy.

Why a capacitor? Batteries generally charge comparatively slowly and inefficiently; it's not a major drawback during constant operation, but when just a few seconds of regenerative braking are being captured, a battery is less efficient than Mazda's electric double-layer capacitor (EDLC), which recharges fully within only a few seconds. The power is generated by a variable-voltage alternator, and a full capacitor charge can run things like the climate control and audio systems for a minute or so.

It may not sound like much, but in real-world driving the minute of charge is often enough to power the vehicle without the battery during engine-off operation (in stop-start mode). Mazda claims i-ELOOP can produce most of the vehicle's electrical power in normal driving conditions, freeing up the power normally used to drive the alternator.

Like the Mazda 6 wagon itself, the i-ELOOP system won't be headed stateside for the foreseeable future. While wagons are something of a risky bet in the modern domestic market, there's a more straightforward reason that Mazda will not be installing i-ELOOP in vehicles bound for America: The current EPA testing cycle does not recognize fuel economy gains that capacitor-based regeneration systems can provide.

The 2012 Paris motor show—or Mondial de l'Automobile, as it is officially known––will take place Sept. 27 through Oct. 14. It occurs every two years, alternating with the Frankfurt motor show in Germany. Paris is a showcase for the latest in design, but automakers will also be showing off their latest concept cars, green cars and supercars.

Andrew Stoy
- Digital editor Andrew Stoy is an avid enthusiast of all cars who has spent the past 15 years writing about the automobile in print, online and for advertising and PR firms.
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